It is due to anthocyanin.
- Anthocyanin is the pigment that gives red apples their vibrant colour. The cool nights of late August and early September trigger the change in the enzymes of the apple skin to change the colour from green to red
- The red pigmentation in the skin and flesh of apple fruits (Malus × domestica Borkh.) is due to anthocyanin accumulation. Anthocyanins belong to a class of molecules called flavonoids, and they are particularly important for fruit quality because redder fruits have a higher market value.
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The presence of red flesh in apple cultivars is caused by the MYB10 gene, a localized genetic protein and transcription factor for anthocyanin pathways.
- Red, purple, and blue fruits and vegetables typically have the highest levels of anthocyanin, including mulberries, black chokeberries, black elderberries, black currants, sweet cherries, blackberries, lingonberries, strawberries, sour cherries, red raspberries, black grapes, plums, blueberries, black beans, red currants, red wine, and red onion. Blueberries, blackberries, raspberries and strawberries are also great sources. Additional foods with a high anthocyanin punch include: Fruits: Black plums, blood oranges, cherries, black and red grapes and pomegranates
HEALTH BENEFIT
- Previous research has linked anthocyanins to various health benefits, including increased longevity, cardiovascular health, cancer prevention and dementia. Anthocyanins may also improve vision and have a neuroprotective effect
- The experiments suggest that anthocyanins, as a functional food component, can aid in preventing obesity and diabetes. Anthocyanins have been credited with the capacity to modulate cognitive and motor function, enhance memory, and prevent age-related declines in neural function.
- anthocyanins may regulate amino acid metabolism to participate in the kidney protection effects.